Pablo Cuevas and Marcos Baghdatis will meet in the quarter-finals of the Aegon Nottingham Open after each surviving major scares on Wednesday.
Second seed Cuevas was on the brink of defeat to Great Britain's Dan Evans, but turned things around to triumph 6-7 (4-7) 7-6 (7-5) 6-4.
Evans got to 15-30 on his opponent's serve when leading 5-3 in the second set and was then broken as he served for the match at 5-4.
Baghdatis, meanwhile, saved two match points in a second-set tie-break before completing a 1-6 7-6 (10-8) 6-4 victory over Sam Querrey, the fifth seed and last year's runner-up in Nottingham.
Top seed Kevin Anderson was a 6-3 7-6 (8-6) winner over Fernando Verdasco and Andreas Seppi beat Adrian Mannarino 6-2 6-3. Mannarino had prevailed in straight sets when he faced Seppi in 's-Hertogenbosch a fortnight ago.
Gilles Muller's strong grass-court form continued as he came from a set down to beat Mikhail Youzhny 6-7 (4-7) 7-6 (7-4) 6-3.
Steve Johnson came through two breakers to beat Vasek Pospisil, while Alexandr Dolgopolov and Dudi Sela recorded respective victories against Frank Dancevic and Benjamin Becker.